This invention relates to fluorescent sensors for chemical analysis.
Optical sensors are used in the determination of the chemical properties of liquid or gas-phase analytes. Existing sensors typically place the sensor material either in the evanescent field of the waveguide or at the tip of an optical fiber. The sensitivity of sensors based on evanescent field excitation is limited by the quantity of fluorescence coupled to the waveguide or fiber structure. The total quantity of fluorescence collected at a photodetector is also limited by inefficiencies associated with coupling light from the source to the optical waveguide or optical fiber. The specificity of fluorescent chemical sensors is limited by interferences associated with chemical reactions between the sensor material and materials other than the analyte.
Needs exist for optical waveguide sensors that can increase specificity, sensitivity and precision of fluorescent chemical sensors.